This invention is applicable to pressure transducers generally, but is particularly applicable to pressure transducers of the general construction disclosed and claimed in the applicant's U.S. Pat. No. 4,141,252, issued Feb. 27, 1979, and entitled "Flush Pressure Transducers for Measuring Pressures in a Flowing Fluid". A pressure transducer of this general construction comprises substantially flat diaphragm means forming a smooth continuous wall, to which fluid pressure is applied, a body backing up and supporting the diaphragm means, such body having an opening therein, the diaphragm means covering such opening and affording a flexible resilient diaphragm across such opening, and sensor means mounted in such opening for sensing the deflection of the diaphragm due to fluid pressure. The sensor means may be of the variable capacitance type, comprising a capacitative electrode spaced behind the diaphragm and supported on an insulator which is mounted in the opening in the transducer body.
While flush transducers of this type are highly effective and useful, it has been found that the fluid pressure causes slight bending of the transducer body, and that such bending introduces anomalies and inaccuracies, particularly at high fluid pressures. This factor imposes a limitation upon the useful pressure range of the pressure transducer. In some cases, the bending can be caused by counteracting fluid pressure introduced on the sensor side of the diaphragm.